title: Silybin inhibits interleukin-1β-induced production of pro-inflammatory mediators in canine hepatocyte cultures.
abstract: Hepatocytes are highly susceptible to cytokine stimulation and are fundamental to liver function. We established primary canine hepatocyte cultures to study effects of anti-inflammatory agents with hepatoprotective properties. Hepatocyte cultures were incubated with control media alone, silybin (SB), or the more bioavailable silybin-phosphatidylcholine complex (SPC), followed by activation with interleukin-1 beta (IL-1β; 10 ng/mL). Inflammatory response was measured by prostaglandin E2 (PGE(2) ), interleukin-8 (IL-8), and monocyte chemotactic protein-1 (MCP-1) production and also nuclear factor-kappa B (NF-κB) translocation. Hepatocyte cultures continued production of the phenotypic marker albumin for more than 7 days in culture. IL-1β exposure increased PGE(2) , IL-8, and MCP-1 production, which was paralleled by NF-κB translocation from the cytoplasm to the nucleus. Pretreatment with SB and SPC significantly inhibited IL-1β-induced production of pro-inflammatory markers and attenuated NF-κB nuclear translocation. We demonstrate for the first time that primary canine hepatocyte cultures can be maintained in culture without phenotypic loss. The observation that hepatocyte cultures respond to pro-inflammatory IL-1β activation indicates hepatocytes as primary cellular targets of extrinsic IL-1β. The ability of SB and SPC to inhibit hepatocyte culture activation by IL-1β reinforces the notion of their hepatoprotective effects. Our primary canine hepatocyte culture model facilitates identification of hepatoprotective agents and their mechanism of action.
authors.affiliation: Research and Development, Nutramax Laboratories, Inc., Edgewood, MD 21040, USA.
authors.forename: A Y
authors.initials: AY
authors.lastname: Au
authors.forename: J M
authors.initials: JM
authors.lastname: Hasenwinkel
authors.forename: C G
authors.initials: CG
authors.lastname: Frondoza
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D004285:Dogs; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism*; D053583:Interleukin-1beta / Q000037:antagonists & inhibitors*; D016209:Interleukin-8 / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D000077385:Silybin; D012838:Silymarin / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D018932:Chemokine CCL2; D053583:Interleukin-1beta; D016209:Interleukin-8; D016328:NF-kappa B; D012838:Silymarin; D000077385:Silybin; D015232:Dinoprostone